Scientists have mapped the eye colour of people in Britain. The most common colour is blue. Thousands of years ago it was brown. Nearly half of people have blue eyes, 30 per cent have green eyes and 22 per cent have brown. Edinburgh is where most blue-eyed people live. Over half of people around Edinburgh have blue eyes. England's southwest has the fewest blue-eyed people. Scientists do not know why places in Britain have more blue-eyed people.

The research said the number of blue-eyed people is increasing. People think they are more attractive. Blue-eyed people are more successful at finding a partner. A researcher said having blue eyes is like a peacock. A colourful peacock gets more mates. People are attracted to the light sparkling in blue eyes. Darker eyes sparkle less. A scientist said: "There is something attractive about blue eyes, maybe because they used to be so rare."